The class of polyamide polymers is broadly well known in the art. A commercial example of this class of polymers is the polyamide illustratively produced from hexamethylenediamine and adipic acid known as Nylon 66. The nature of the reaction product of a carboxylic acid or related compound will vary, however, depending upon the chemical nature of the acid compound and the amine.
The reaction of a ketobenzoic acid, i.e., benzoylbenzoic acid, and diamines is shown by Hovey et al, U.S. Pat. Nos. 2,149,678 and 2,195,570. The reaction of aromatic dicarboxylic acids and photosensitive diamine compounds is shown by Nakama et al, U.S. Pat. No. 4,595,745. Caldwell et al, U.S. Pat. No. 3,408,334, describe the reaction of dicarboxylic acids and diamines in the presence of a tin compound as catalyst. Reaction of .alpha.,.beta.-unsaturated aromatic dicarboxylic acids and primary and secondary diamines is disclosed by Conciatori, U.S. Pat. No. 3,637,602. The production of polyamideimides by reactions including that of a diacid and polyamides is shown by Emerick et al, U.S. Pat. No. 3,778,411. The use of a dicarboxylic acid of additional functionality, 4-oxoheptanedioic acids, in the production of polymers is shown by Ferstandig, U.S. Pat. No. 2,987,502, but reaction was with a polyhydroxylic alcohol and the product was a polyester.
A class of compounds that functions in some ways similar to dicarboxylic acids is the class of 1,6-dioxa[4.4] spirodilactones. The simplest member of this class, 1,6-dioxaspiro[4.4]nonane-2,7-dione, is known and has been prepared, among other procedures, by the process of Pariza et al, Synthetic Communications, Vol. 13(3), pp. 243-254 (1983). These spirodilactones have demonstrated utility as curing agents to produce cured compositions which do not shrink upon curing. This property probably results from opening of the spirodilactone rings during the curing process, Knowles, J. Appl. Polymer Science, Vol. 10(6), pp. 887-889 (1966). It is characteristic of the spirodilactone ring system that reaction with active hydrogen compounds tends to produce ring-opened products, as further evidenced by the above Pariza et al article. See also Cowsar et al, U.S. Pat. No. 4,064,086. One reaction of 1,6-dioxaspiro[4.4]nonane-2,7-dione in which a ring system is maintained is described and claimed in copending U.S. patent application Ser. Nos. 172,052, filed Mar. 23, 1988 and 245,618 filed Sept. 16, 1988 wherein the spirodilactones are reacted with hydroxy-containing primary amino compounds to produce monomeric substituted spirodilactams.
The polyamide polymers of the present invention are thermoplastic polymers as are many other polymeric polyamides. However, because of the relatively low melting point or glass transition temperatures exhibited by many polymeric polyamides, the thermoplastic polyamides are not generally useful as engineering thermoplastics where exposure to elevated temperatures is likely to be encountered. It would be of advantage to provide novel polymeric polyamides having relatively high glass transition temperatures. It would be of further advantage to provide processes employing dicarboxylic acid compounds or alternatively spirodilactones to produce such polymeric polyamides.